Improvement in steam-boilers



UNTTED STATES PATENT OFFICE.

CHARLES T. BOARDMAN, OF FAVTUOKE'I, RHODE ISLAND.

IMPROVEMENT IN lSTEAM-BOILERS.

Specilication forming part or" Letters Patent No. 47,790, dated May 23, 1865.

To all whom it r11/ay concern,.-

Be it known that I, CHARLES T. BOARD MAN, of Pawtucket, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Steam-Boilers; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specication, in which- Figure l is a central longitudinal section ot' my invention. Fig. 2 is a transverse vertical section ot' the same in the plane indicated by the line a: :c in Fig. l. Fig. 3 is a horizontal section ot' the same in the plane indicated by the line y y in Fig. l.

Similar letters of reference indicatev corresponding parts in lhe several figures.

This invention consists in two plain cylindrical boilers arranged side by side, and one inclined tubular boiler arranged below the rear portions `of the said cylindrical boilers and connected with them by means of laterally -inclined waterlegs, such arrangement forming a boiler well adapted for the economical generation of steam, and aording provision for the collection ot' sediment in a comparatively cool part ot the boiler.

It also consists in a novel arrangement of the ilues and settingof such a boiler, and in a novel arrangement oi' an airduct and ,mixing-chamber for the admission of air from the ash-pit to mix with the gases of combustion in rear ot the bridge-wall ot' the lire-place ot' such a boiler.

To enable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A A are the two plain cylinder-boilers, arranged side by side.

B is the tubular-boiler,havingits tubes at a extending through it in a longitudinal direction. This boiler is about half the length of A A, and is arranged centrally under the lower parts thereof, as shown in Fig. l. It is 1 arallel with A A in a vertical direction, but has a downward inclination from front to rear, :s shown in Fig. 1.

C (l are the laterally-inclined water-legs connecting the two boilers A A with the boiler B. These legs are of cylindrical form, and two separate ones are employed to conneet each of the boilers A A with B, one near the front and the other near the rear end of the latter. A

D D Dl D2 are outer walls of the setting, and E is pier erected below the boilers A A, and a shortdistance infront of B, extendingfrom the foundation of the setting upward to the boilers A A, but not extending all across the space between the side walls, D D, of the sitting. From the sides of this pier It two vertical parallel walls, F F, extend backward to within a short distance ofthe rear wall, D', ofthe setting, the said walls F F extending upward from the foundation to the boilers A, as shown in Fig. 2. A space should be left between th es e walls and the sides of the boiler B.

G is the fire-place, and L the ash-pit.. In rear of the grate is the ordinary bridge-wall, J, and between this and the pier E is a mixing-chamber, H, into which air to mix with the gases of combustion is admitted in an upward direction from the ash-pit through a duct or ducts, b, in a bridge-wall, I, behind and somewhat lower than J.

The operation is as follows: The gaseous products of combustion pass from the replace over the bridge-wall J into the mixingchamber H, where they are met by the air issuing upward from the duct or ducts b, and in which a thorough mixing ot' the air and gases is effected, and the ignition of the combustible portions of the gases not previously ignited takes place before the gases can escape through theopenings c c at thesides of the pier E, which are the only outlets from the said chamber. The llame and heated products pass thence through the tlues d d, between the walls F F and D D, and under the outer portions ofthe bottoms of the boilers A A and through the openings e e, Fig. 3, at the ends of the walls'F F, and return in a backward direction through theilue space g,formed between the walls F F around the tubular boiler B and water-legs O C, and under the boilers A A,vand after passing into the space f, between the front of the boiler B and the pier E, return in arearward direction through the tubes a a of the boiler B whence they are collected in a breeching at the rear of the said boiler and escape to the 11p-take or chim ney.

, The water in the boiler B and legs C U is heated to such an extent by heat which in the ordinary mode of setting two plain cylinderA boilers would he lost that considerable steam 'set' in the ordinary way, and in this consists one ot' its merits.

What I claim as iny invention, and desire to secure by Letters Patent, is- Y 1. The arrangement of the two cylindrical boilers A A,the tubular boiler B, and the lat-- erally-inelined Connecting water-legs C C, sub

stantially as and for the purpose herein specitied.

2. In combination with the two cylindrical boilers A A, tubular boiler B, and walls D D, of their setting, the pier E, and connected parallel upright walls F, arranged substantially as herein described.

3. The gas and air mixing eh amber H, bridgewall I, and air duet or duets b, in combination with each other and with the bridge-wall J, pier E, and ash-pit L, substantiallyr as herein set forth.

4. The combination of the boilers A A B, tire-place G, mixin g-ehamber H, side iiues, d d, and return-flue g, the whole arranged substantially as and for the purpose herein specified.

C. T. BOARDMAN.

Witnesses J. \V. Gooi/riss,

G. W. REED. 

